CVE-2026-101338
When a SVCB or HTTPS RR has filled the wire format RDATA up to the brim, another ECH parameter may…
- Risk score
- 57/100
- CVSS
- 8.7 v4.0
- Exploit chance (30 days)
- 0.3%
- Published
- 14 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- When a SVCB or HTTPS RR has filled the wire format RDATA up to the brim, another ECH parameter may overwrite the stack, and once beyond the limit, the base64 decoder can write attacker controlled data of unlimited size. Zone files which are written out by NSD itself, such as for zones for which the NSD instance is sec…
- Affected
- See advisory
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 8.7 high
References
Original description
When a SVCB or HTTPS RR has filled the wire format RDATA up to the brim, another ECH parameter may overwrite the stack, and once beyond the limit, the base64 decoder can write attacker controlled data of unlimited size. Zone files which are written out by NSD itself, such as for zones for which the NSD instance is secondary, will not be formatted like this. The zone file must be fed to NSD directly, (but it could come, for example, from an operator controlled provisioning system).
Last activity 14 Oct 2026. Patch Forecast updates every hour.